Five salmonella cases in Texas appear to be related to the national outbreak involving a West Coast poultry producer, a state health official said Wednesday.

"The Texas cases have the same strain of salmonella, but we don't know if they have eaten the Foster Farms chicken," said Chris Van Deusen, spokesman for the Texas Department of State Health Services.

Nearly 300 people in 18 states have been sickened since about July by an outbreak of Salmonella Heidelberg traced to raw chicken from three sites run by the private California poultry producer, said Barbara Reynolds, a spokeswoman for the Centers for Disease Control and Prevention.

Federal food safety workers who monitor dangerous bacteria have been recalled from furlough to track an outbreak of salmonella linked to Foster Farms chicken that has hospitalized a high proportion of victims, including some with hard-to-treat infections.

Foster Farms has poultry plants in Oregon, Washington, California and Alabama. Company officials say they are working with federal authorities to try to identify the source of the salmonella outbreak. None of their products have been recalled yet.

About 42 percent of patients reporting complete information have been hospitalized, about double the proportion typically expected from a salmonella outbreak, Reynolds said. Of 183 complete cases, 76 patients have been hospitalized. Among those, many infections appear to be resistant to the most common antibiotics used to them, she added.

Of the five Texas cases, three were not hospitalized and the other two have not been identified by state officials investigating the outbreak, Van Deusen said. The state does not identify where the victims reside.

At least seven different strains of Salmonella Heidelberg have been tied to the outbreak, which led CDC officials on Tuesday to recall 30 staffers, including 10 who work for the agency’s PulseNet team, which monitors the electronic fingerprint of dangerous foodborne bugs. They’d been on furlough because of a government shutdown stretching into its second week.

“We had said from the beginning that we were monitoring 30 outbreaks of foodborne illness,” Reynolds said. “This is one of them. It’s breaking loose now.”

The CDC move follows a USDA public health alert issued Monday for the raw chicken products. The agency’s Food Safety and Inspection Service has been unable to identify specific products or a specific production period for the potentially tainted chicken, but said that affected meat bears one of three establishment numbers inside a USDA inspection mark or elsewhere on the package.

The numbers are P6137, P6137A and P7632.

The chicken was distributed to retail outlets mainly in California, Oregon and Washington, but illnesses have been reported in 18 states. Those include Alaska, Arkansas, Arizona, California, Colorado, Connecticut, Florida, Hawaii, Idaho, Illinois, Michigan, North Carolina, Nevada, Oregon, Texas, Utah, Washington and Wisconsin.

The cases may share some overlap with an outbreak of Salmonella Heidelberg tied to Foster Farms chicken announced in May, Reynolds said. But most of the cases occurred since July.

The previous outbreak was declared over in July after 134 people in 13 states became sick, including 33 who were hospitalized. No deaths have been reported in either outbreak, CDC said.Foster Farms officials said they’ve been working with federal officials investigating the source of salmonella at their sites. No recalls have been issued for any specific food products.

Salmonella can be present in all raw chicken and that consumers should cook poultry thoroughly – to 165 degrees – to kill any illness-causing bacteria. CDC officials stopped short of advising consumers not to eat the potentially contaminated chicken, but said that good cooking, hand hygiene and kitchen practices should be followed.

Foster Farms officials said that the chicken is safe to eat when properly cooked and handled. Consumers can call the firm's hotline at 800-338-8051 or visit the website.

Salmonella Heidelberg is a common strain that causes illness that can be life-threatening in people with weak immune systems such as children, the elderly and those with cancer or HIV infection. Most common symptoms include diarrhea, abdominal cramps and fever within eight hours to three days after eating the contaminated product. Chills, headache, nausea and vomiting can last up to a week.